1. Field of the Invention
The present invention relates generally to locks and, more particularly, to an improved lock for bicycles, motorcycles, scooters, mopeds and the like.
2. The Prior Art
The numbers of bicycles, motorcycles scooters, mopeds and the like in daily use have increased dramatically lately. Some of these items are now quite expensive. Thefts of these items also have increased dramatically. These items, once stolen, represent not only considerable loss to their owners, but also are difficult to trace and to recover. Professional and some not so professional thieves nowadays frequently employ a bolt cutter, a long lever or the like to sever or break quickly and quietly cables, chains or other devices used to secure bicycles and the like to posts or other fixed objects. To guard thereagainst, large heavy locks have been developed comprising rigid U-shaped shackles and cross bars designed to attach to the ends of the shackles. See U.S. Pat. Nos. 3,924,426; 3,967,475 and 4,155,231. These devices offer good resistance to bolt cutters, hack saws and the like.
More recently, a bicycle lock featuring a replaceable lock cylinder which may be identical to one used in the home or office and operable by the same key, has been developed. See the U.S. Pat. No. 4,545,224.
The present invention is an improvement over the Bicycle Lock and Bracket disclosed and claimed in U.S. Letters Pat. No. 4,155,231, granted May 22, 1979, and over the Bicycle Lock disclosed and claimed in U.S. Letters Pat. No. 4,545,224, granted Oct. 8, 1985, both assigned to a common assignee, KBL Corporation of Boston Massachusetts. See also U.S. Pat. No. 4,730,470, Zane et al, "Security Lock," granted Mar. 15, 1988.
The known art of locks in general goes back centuries. Locks specifically designed for bicycle security were introduced more recently. For various relevant locks, see the U.S. Pat. No. 187,362, entitled "Shackles," that was granted to H. W. Dilg on Feb. 13, 1877. It discloses a device whereby prisoner's ankles may be shackled. German Patent No. 105,187 issued in 1898 and discloses a bicycle lock in which the legs of a U-shaped shackle must be squeezed together before they are insertable into a cross piece. German Patent No. 111,976 is an addition thereto featuring an improvement in locking the same with the aid of a Chubb lock. U.S. Pat. No. 1,036,992, granted to G. S. Franki on Aug. 27, 1912, discloses a padlock featuring a cylindrical body with a cylindrical bore. A shackle extends through slots and into the base and is secured therein by a pin on the one hand and by another pin of a locking member. German Patent No. 824,896, issued in 1951, discloses a U-shaped bicycle lock in which a spring and tumbler device engages one leg of a shackle, securing thereby the shackle to a cross piece. And U.S. Pat. Des. Nos. 238,548 granted to R. N. Seaken on Jan. 27, 1976 and No. 4,085,600 granted to A. E. Bindari on Apr. 25, 1978 both disclose bicycle locks featuring a locking mechanism in the end of the cross piece.
A combined carrying and locking device for a cycle is disclosed in U.S. Pat. No. 4,256,322; while an antitheft device for a bicycle is shown in U.S. Pat. No. 4,271,690. U.S. Pat. No. 4,324,119 teaches a passive wheel lock for bicycles; U.S. Pat. No. 4,426,861 features a brake lock for motorcycles; and U.S. Pat. No. 4,524,591 shows a lock device for chain driven vehicles. A pick-proof locking system is shown in U.S. Pat. No. 4,584,855; while a combined vehicle and assembly locking and wrenching apparatus is disclosed in U.S. Pat. No. 4,674,306. U.S. Pat. Nos. 4,823,566 and 4,823,567 disclose padlock and locking mechanisms. A self-retracting security system for bicycles is illustrated in U.S. Pat. No. 4,870,843; while a shackle lock is disclosed in U.S. Pat. No. 4,881,387. The art is thus crowded yet remains open for improvements.